.\" Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
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.Dd April 7, 1999
.Dt TRIMDOMAIN 3
.Os
.Sh NAME
.Nm trimdomain
.Nd "trim the current domain name from a host name"
.Sh LIBRARY
.Lb libutil
.Sh SYNOPSIS
.In sys/types.h
.In libutil.h
.Ft void
.Fn trimdomain "char *fullhost" "int hostsize"
.Sh DESCRIPTION
The function
.Fn trimdomain
removes the current domain name from the passed
.Ar fullhost
name by writing a
.Dv NUL
character over the first period of the passed name.
The current domain
name is determined by calling
.Xr gethostname 3
and removing everything up to the first period.
The name is determined
the first time this function is called and is cached for future use.
.Pp
The
.Fn trimdomain
function will only trim the domain name if the passed
.Ar fullname
ends with the current domain name and if the length of the resulting host
name does not exceed
.Ar hostsize .
.Pp
If the passed
.Ar fullname
is actually a
.Dv DISPLAY
specification of the form
.Sm off
.Ar host . domain : nn Oo .
.Ar nn
.Oc
.Sm on
and the domain name is the same as the local domain name,
.Fn trimdomain
will remove the embedded domain name, copying the screen and display
numbers to the end of the base host name and resulting in
.Sm off
.Ar host : nn Op . Ar nn .
.Sm on
.Sh RETURN VALUES
The
.Fn trimdomain
function does not return a value.
.Sh SEE ALSO
.Xr gethostname 3
.Sh HISTORY
The function
.Fn trimdomain
first appeared in
.Fx 3.2 .
